Filling system with post-dripping prevention

ABSTRACT

The invention relates to a filling system filling beverages into containers and comprising a valve controlling the feed of filling material and mounted a distance above the discharge aperture in order that there shall remain a discharge surface between the valve and the discharge aperture, further comprising a post-dripping precluding device preventing post-dripping of the filling material when the valve is closed, and it is characterized in that the post-dripping precluding device enhances the drop detachment of the filling material from the discharge surface of the discharge zone.

[0001] The present invention relates to a filling system defined in the preamble of claim 1.

[0002] Filling systems are used in filling machines to fill beverage containers such as bottles or cans with beverages such as mineral water, fruit juice or beer. To control the filling procedure, such filling systems are fitted with valves mounted in the supply path of the filling material.

[0003] It is known as regards the case of the above filling control valve being designed other than a foot valve, that drops of filling material will remain at the walls on the valve discharge side and be dripping once the valve has been closed. This dripping arises some time after closing the valve, and as a result dripping may even take place when a beverage container no longer shall be situated below the filler system's discharge aperture. On one hand there may ensue filling inaccuracies. On the other hand the falling drops reach the filling machine floor, or they will soil the filling machine below the filling system. Especially as regards high-calorie beverages, the dripping material provides a nutrient substrate jeopardizing the sterility of the filling procedure. Consequently frequent cycles of cleaning must be carried out to meet the filling sterility requirements. In general however cleaning entails interrupting filling and thus interferes with economical operation of the filling machine.

[0004] The state of the art counters the above post-dripping problem by fitting the filling system with devices preventing any remnant drops from falling. Illustratively the discharge aperture of the filling system is fitted with a sieve which however negatively affects the flow of the filling material because entailing undesired eddies that in turn may produce foaming of the filling material inside the container. When filling fruit juices—which are especially likely to contain fruit fibers—the use of a sieve is precluded anyway because it would quickly clog.

[0005] Another drawback of the known post-drip prevention devices is that the drops may fall in spite of them. While the post-dripping problem is being palliated, namely fewer drops shall contribute to soiling the filling machine, the intrinsic problem on the other hand remains unsolved.

[0006] Therefore the objective of the present invention is to create a filling system overcoming the above post-dripping problems.

[0007] This problem is solved by the filling system of the invention defined by the features of claim 1.

[0008] The basic concept of the invention is not to interfere with the dripping of drops forming on the discharge surface, but on the contrary to enhance or to force this dripping of the filling material from the discharge surface. Accordingly the filling system of the invention includes a post-dripping precluding device that enhances early-dripping of the filling material. The discharge surface shall be understood to be at least the filling system's inside wall zone running at the discharge side of the filling-material control valve as far as the discharge aperture.

[0009] Said post-dripping precluding device assures that after the filling-material control valve moves into its closed position, any drops present shall fall at once and hence shall reach the beverage container still situated below the discharge aperture. All drops shall have fallen before the beverage container is removed and as a result the filling machine shall not be soiled on account of time-delayed dripping.

[0010] Advantageous embodiments of a filling system of the invention are stated in the sub-claims.

[0011] As defined in claim 2, the said post-dripping precluding device advantageously assumes the form of a hydrophobic discharge surface of at least the discharge zone on the valve's discharge side. Because the discharge surface of the invention is hydrophobic, drops are unable to adhere to the discharge surface, instead immediately detaching off it as soon as the valve shuts off the supply of filling material. The term “hydrophobic” is to be construed broadly as denoting the filling material being repelled by the surface.

[0012] Advantageously and as claimed in claim 3, the discharge surface shall be made of teflon. Teflon exhibits the desired hydrophobia and moreover is economical, unobjectionable with respect to foodstuffs and also is easily machined. It is also stable still at the temperatures of hot filling and it is insensitive to common cleansing means.

[0013] Selectively merely the surface of the discharge zone may be made of teflon, or a portion of the filling system may be a thick, hollowed body made of teflon of which the inside surface shall constitute the discharge surface. However the entire filling system may also consist of teflon.

[0014] Claim 4 advantageously proposes an alternative to this hydrophobic surface in that the post-dripping precluding device precluding post-dripping shall be a micro-structured discharge surface causing a lotus effect. It is known that appropriate microstructured surfaces will reduce the contact area with liquid drops. Accordingly this alternative also reduces the adhesion of the filling material to the discharge surface and said filling material will immediately drip off. In this manner there will be effective suppression of time-delayed dripping. In this design as well all wall zones of the filling system that shall be in contact with the filling material may be microstructured surfaces.

[0015] Claim 5 proposes a further advantageous alternative of the said post-dripping precluding device being designed to induce vibrations in the filling system's discharge surface. It is well known that the drops on a surface which is both slanted and vibrating shall rapidly drop off it. When the surface is made vibrate, time-delayed dripping will therefore be precluded

[0016] Advantageously and as stated in claim 6, the post-dripping precluding device of the invention shall be in the form of mechanical means impacting the filling system. Such means, for instance in the form of a displaceable lever, can be initiated in synchronized manner for instance by the closing of the valve. As regards rotary filling machines however the impacting means also may be a stationary component with which the rotary filling system will periodically collide during rotation.

[0017] Alternatively claim 7 advantageously proposes that the post-dripping precluding device shall apply acoustic waves to at least the filling system's discharge zone. Therefore an appropriate sound source must be mounted with acoustic access to the filling systems discharge zone. The acoustic source may be operated as needed continuously or be timed into operation upon valve closure.

[0018] A further advantageous alternative is stated in claim 8, namely the post-dripping precluding device being in the form of a piezoelectric surface driven into vibrations of voltage-controlled amplitude and frequency. Said voltage must be therefore appropriately selected. Again, in this embodiment only the surface need be piezoelectric, or else a solid portion of the filling system of which the inside surface shall constitute the discharge surface.

[0019] Claim 9 advantageously proposes that the post-dripping precluding device shall be designed in such manner that an expelling gas may be forced onto the discharge surface. For that purpose the filling system illustratively is fitted with an annular gas-expelling aperture directly underneath the valve seat which transmits the expelled air into the discharge zone and onto the discharge surface. Any generated drops will be blown away by the expelled air.

[0020] Claim 10 advantageously provides a perforation in the discharge surface, a blow-off gas passing through said perforations into the discharge zone. According to claim 11, the discharge surface advantageously consists of a porous sintered material.

[0021] Further details and features of the invention are stated in the description below elucidating illustrative embodiments in relation to the attached drawings.

[0022]FIG. 1 shows a section of a filling system of the invention fitted with a post-dripping precluding device precluding post-dripping, and

[0023]FIG. 2 is a section of a second filling system of the invention.

[0024]FIG. 1 shows a filling system 1 communicating through an omitted filling-material feed and an omitted return gas duct with the supply container of a filling machine that may be of conventional rotary or linear design. An in-line meter at the filling material feed may detect the flow through it. The quantity of filling material having entered a container 5, in this instance a bottle, may be determined by a integration over time and be used to control the filling procedure. The container 5 is affixed during filling by omitted retaining means acting on the container base so as to be sealed against a container seal 6 at the filling system 1.

[0025] The filling-material feed issuing into the container 5 in this embodiment is controlled by a valve 9 which is displaceable in height and is supported in pressure-proof sealed manner, this pressure-tight sealing during permissible height-displacement typically being implemented by a sliding seal. When the valve 9 has been fully lowered, the annular seal 12 mounted on the undercut 11 of said valve comes to rest against an associated annular wall segment of the filling chamber 7 constituting the valve seat 13. FIG. 2 shows the valve 9 in its lowered, i.e. sealing/closed state.

[0026] The wall segment of the filling chamber 7 running from the discharge aperture 14 as far up above the valve seat 13 is fitted with illustratively a hydrophobic teflon layer 15. Filling material adheres only very poorly to this surface.

[0027] Moreover the entire chamber wall may be made hydrophobic instead of merely the lower wall segment of the filling material chamber 7 being fitted with a hydrophobic layer 15. Such an extension of hydrophobia would be advantageously for instance as regards cleaning, because both the filling material and the cleaning substances being then hampered in their adhesion. FIG. 2 shows a second filling system 1 of the invention consisting of an upper segment 20 and a lower segment 21 which are connected in this instance by screw threads 22. As an alternative, such connection however also may be carried out permanently by bonding or the like.

[0028] The lower segment 21 of the filling system 1 is made of a piezoelectric material to which a voltage is applied by conducting plates 23 mounted sideways to the filling system 1 and connected through conductors 24 to the two terminals of a voltage source 10. When a voltage is present, the lower segment 21 of the filling system 1 is made to vibrate as a function of the frequency and amplitude of the drive voltage. The vibration of the lower segment 21 must be taken into account when selecting the connection to the upper segment 20.

[0029] Moreover the entire filling system 1 may be made of a piezoelectric material. In that design there is no need to appropriately connect two segments. Alternatively to this integral design, only one piezoelectric layer might be needed for the lower wall zone or the entire wall zone of the filling material chamber 7, in the manner discussed above in relation to a hydrophobic layer 15 in FIG. 1. In such a design the voltage-applying conducting plates then would be mounted underneath the said layer and a multi-layer structure would ensue.

[0030] An acoustic source 25 is shown in dashed lines in FIG. 2 and has access to the discharge zone 26 for the purpose of unimpeded acoustic output, being able to load this zone 26 with acoustic waves. Both the power supply to the acoustic source 25 and its feed lines are omitted for the sake of clarity.

[0031] Moreover a second or an arbitrary number of acoustic sources 25 may be used, or several of the above steps preventing post-dripping may be combined, for instance by providing one acoustic source 25 in conjunction with one hydrophobic layer 15 of at least one discharge zone 26 List of reference numerals:  1 filling system  5 container  6 container seal  7 filling-material chamber  9 valve 10 voltage source 11 lower side 12 annular seal 13 valve seat 14 discharge aperture 15 layer 20 upper segment 21 lower segment 22 threaded connection 23 conducting plates 24 conductors 25 acoustic sources 26 discharge zone 

1. A filling system to (1) fill beverages into containers (5) and comprising a valve (9) controlling the feed of filling material and mounted a distance above the discharge aperture (14) in such manner that a discharge zone (26) including a discharge surface remains between the valve (9) and the discharge aperture (14), further comprising a post-dripping precluding device precluding post-dripping of the filling material when the valve (9) is closed, characterized in that said post-dripping precluding device is designed to enhance the drop detachment of the filling material from the discharge surface of the discharge zone (26).
 2. Filling system (1) as claimed in claim 1, characterized in that the post-dripping precluding device is designed as a hydrophobic discharge surface (15) of at least the discharge zone (26).
 3. Filling system (1) as claimed in claim 2, characterized in that the discharge surface (15) is made of teflon.
 4. Filling system (1) as claimed in claim 1, characterized in that the post-dripping precluding device is designed as a micro-structured discharge-surface (15) exhibiting a lotus effect.
 5. Filling system (1) as claimed in claim 1, characterized in that the post-dripping precluding device is designed to drive the discharge surface (15) into vibrations.
 6. Filling system (1) as claimed in claim 5, characterized in that the post-dripping precluding device is in the form of mechanical elements impacting the filling system (1).
 7. Filling system as claimed in claim 5, characterized in that the post-dripping precluding device may apply acoustic waves to at least the discharge zone (26).
 8. Filling system (1) as claimed in claim 5, characterized in that the post-dripping precluding device is designed as a piezoelectric discharge surface (15) to which a voltage is applied.
 9. Filling system (1) as claimed in claim 1, characterized in that the post-dripping precluding device is designed in such a way that a blowoff gas can be applied to the discharge surface (15).
 10. Filling system (1) as claimed in claim 9, characterized in that the discharge surface (15) is fitted with a perforation through which the blowoff gas can be applied to the discharge zone (26).
 11. Filling system (1) as claimed in claim 10, characterized in that the discharge surface (15) consists of a porous, sintered material. 